Floating dry dock for small boats



NOV. 26, 1968 J N 3,412,702

FLOATING DRY DOCK FOR SMALL BOATS Filed July 5. 1966 United StatesPatent 3,412,702 FLOATING DRY DOCK FOR SMALL BOATS James M. Mann, 617 N.Florida Ave, Tarpon Springs, Fla. 33589 Filed July 5, 1966, Ser. No.562,902 1 Claim. (Cl. 114-46) ABSTRACT OF THE DISCLOSURE A floating drydock for small boats comprises an elongated cradle adapted to support aboat thereon. Two elongated floats or pontoons extend along oppositesides of the cradle and are flexibly connected with the cradle bylaterally projecting arms attached thereto and spaced therealong, thearms being pivotally connected to the cradle at the outer ends thereofso that when the pontoons rotate about their longitudinal axes towardsone another the arms are swung to lower the cradle into the water andwhen the pontoons rotate about their axes outwardly from one another thearms swing in an upright position to raise the cradle from the water.The pontoons rotate about their axes when they are drawn towards oneanother and about the pivotal connection between the arms and the cradleby a drum and cable arrangement which also controls spreading of thepontoons from one another which causes lowering the cradle into theWater.

The present invention relates to a floating dock particularly suitablefor dry storage of small boats.

A principal object of the present invention is the provision of a newand improved floating dock for the storage of small boats above thesurface of the water and which comprises two spaced parallel extendingpontoon-like floats supporting a boat cradle therebetween by flexibleconnections so that rotation of the pontoons about their longitudinalaxes in directions away from one another the cradle is raised and whenthe pontoons rotate about their axes towards one another the cradle islowered into the water, and having means for rotating the pontoons asdesired so that a boat may be floated over the cradle and the cradlethen elevated above the surface of the water by rotation of thepontoons. By rotating the pontoons as described, the surfaces thereofmay be positioned for convenient cleaning because all of the wettedsurfaces thereof are exposed during rotation of the pontoons in raisingand lowering the boat cradle. Furthermore, the pontoon rotatingmechanism is normally above the water and is thereby not subjected tomarine growth and the like.

Other objects and advantages of the invention will be apparent from thefollowing description of a preferred form thereof, reference being madeto the accompanying drawings wherein:

FIG. 1 is a perspective view of a boat dock embodying the invention;

FIG. 2 is a fragmentary schematic view of the cable. arrangement foroperating the pontoons of the dock;

FIG. 3 is an end view in elevation of the boat dock; and

FIG. 4 is a fragmentary view of a part of the cable arrangement shown inFIG. 2.

Referring to the drawings, a boat dock is shown which is adapted tosupport a relatively small boat which is indicated at B. The dock 10comprises a boat cradle 11 which is supported by elongated buoyantmembers or pontoons 12, 13 which are pivotally attached to oppositesides of the cradle, the points of attachment being along the innersides of the pontoons. A crank and drum means 14 is provided by whichthe pontoons may be rotated about their pivots to raise and lower thecradle 11 from beneath the surface of the water to a position above theWater to thereby permit a boat to be floated over the submerged cradleand then elevated above the water on the cradle for dry storage. Thedock is suitably anchored in the water by means, not shown.

The cradle 11 comprises two spaced, parallel side members 15, 16, whichare inter-connected by cross members 17 to provide a rigid rectangularframe suitable for receiving thereover boats of the type to be supportedby the dock. Two support bars 20, 21 are provided between the rear mostcross members 17 to form a support for the stern of the boat.

Six upright posts 23, 24, 25, 26, 27 and 28 are provided at the ends andintermediate portions of the side members 15, 16, as shown, and theseposts are provided with ring 'form link members 30 by which the cradleposts are pivotally attached to the pontoons 12, 13.

The pontoons 12, 13 may be formed of any suitable type of floatationstructure such as hollow metal or fibre glass shells or of a floatationmaterial such as a Styrofoam. In the form shown, the pontoons 12, 13 areformed of hollow fibre glass shells and each of which has formedintegral therewith upwardly extended legs 35. The legs 35 are eachpivotally attached to the respective posts 23-28 by a ring form linkmember 36 looped through each of the respective links 30 so that thepontoons are flexible or pivotally attached to opposite sides of thecradle 11 on common axes which run parallel to the side members 15, 16of the cradle. As may be seen in full lines in FIG. 3, when the pontoons12, 13 are in the position with the legs 35 thereof upright, the cradle11 is supported above the surface S of the water, and when thefloatation members are rotated about their pivots outwardly from thecradle 11, the cradle is lowered beneath the surface of the water, asindicated in broken lines. When the pontoons 12, 13 are drawn inwardlytowards the sides of the cradle the pontoons rotate about their axes indirections from one another and swing the arms 35 upwardly and raise thecradle above the surface of the water.

Referring to FIG. 2, the pontoons 12, 13 are adapted to be rotated inunison about their pivots by the crank and drum means 14 which issupported on the top of post 24, which extends to a convenient height.In the form of the invention shown, cables 40, 41, 42 are attached tothe rear, central and forward portions of the Wall 12a of the pontoon 12and cables 43, 44 and 45 are similarly attached to the wall 13a of thepontoon 13. For sake of clarity, the cables are not shown in FIGS. 1 and3, and reference is made to FIG. 2, for a diagrammatic showing thereof.Cable 40 is reeved about pulleys 46-, 47 which are suitably attached tothe side frame member 15 to lead the cable to a ring 50 of a doublepulley structure 51 to which one end of the cable 40 is secured. Cable41 is attached at one end to the pontoon 12 and the other end is reevedbeneath a pulley 52 pivotally attached to side member 15 and the otherend attached to the ring 50. Cable 42 is reeved about pulleys 53, 54which are pivotally attached at the forward end and central portionsrespectively of the side member 15, and its end is attached to ring 50,as shown.

One end of each of the cables 43, 45 is attached to opposite ends of thewall 13a of the pontoon 13 respectively and are reeved about pulleys 55,56 and 57, 58, respectively, which are suitably attached to the frameside member 16. Cable 44 is likewise attached to the ring 60 and isguided by a pulley supported on the central portion of frame member 16but which has not been shown to avoid obscuring other parts of thestructure,

and it is to be understood that this pulley is similar in function topulley 52.

The pulley structures 51, 61 form the moving pulleys of block andtackles 63, 64 respectively and are adapted to move towards and from thepontoons 12, 13 when the drum 14 is rotated one direction or the other.The pulley 51 is arranged opposite a double pulley structure 64 which issecured to the cradle member 16 and the pulleys 51, 64 comprise theblock and tackle 63 which includes a cable 66 having one end attached tothe drum 14 and is reeved about a pulley 67, suitably attached to thecradle member 15, and arranged about the pulleys 51, 64 in aconventional block and tackle manner, the other end of the cable beingsecured to a ring 70 on the pulley 61.

A cable 71 has one end attached to the drum 14 and is reeved about apulley 72 attached to the frame member 15 and leads to the double pulley61 comprising the movable pulley of the block and tackle 64. The cable71 leads from the pulley 61 to a pulley 74 which is secured to cradlemember 15 and which forms the fixed pulley of the block and tackle 64.The cable 71 is reeved on the pulleys 61, 74 in a conventional block andtackle arrangement and the end of the cable is secured to a ring 75 tothe pulley 74.

The drum 14 is adapted to be rotated by crank 76 and preferably, areleasable ratchet mechanism, not shown, is adapted to prevent rotationof the drum in a direction to unwind the cables 66, 71. The ratchetmechanism is well known, and there-fore it is not shown,

By winding the drum 14 by crank 76, the boat operator can draw thepontoons 12, 13 inwardly about their pivots 30, 36 from the positionsshown in dotted lines in FIG. 3 to the full line positions and therebycause the arms 35 to elevate the cradle 11 and boat B thereon in themanner shown. To lower the cradle beneath the water, the drum 14 isunwound and the weight of the boat and cradle causes the cradle to belowered as the pontoons rotate inwardly about their longitudinal axes tothe position shown in dotted lines, whereupon the boat may be floatedfrom over the cradle.

It will be seen that with the arrangement of the pontoons shown that thewetted surfaces thereof are available for convenient cleaning thereof toprevent excessive collection of moss, scum, bamacles and the likethereon, and that when the cradle is raised, the pulley and cables foractuating the pontoons are out of the water.

It will be understood that although but one form of the invention hasbeen shown, other forms, modifications, and adaptations thereof may bemade, all falling within the scope of the claim which follows.

I claim:

1. A floating boat dock comprising, two spaced parallel extendingelongated float members, a boat support cradle between said floatmembers and substantially coextensive with said float members, meansflexibly connecting one side of said cradle to one of said float membersadjacent opposite ends of said cradle for supporting the end portions ofsaid cradle by said one float member and to permit rotation of saidfloat member relative to said cradle, means flexibly connecting the sideof said cradle opposite said one side to the other of said float membersadjacent opposite ends of said cradle for supporting the end portions ofsaid cradle by said other float member and to permit rotation of saidone float member relative to said cradle, said float members, whenbuoyed in a body of water and disposed in a given angular positionsabout their pivots being adapted to support said cradle and a boatthereon above the surface of the water, said cradle adapted to belowered between said floats and beneath the surface of the water whensaid floats are rotated to a different angular position than said givenpositions, and means for rotating said float members in oppositedirections about their axes to raise and lower said cradle above andbelow the surface of water on which said boat dock floats.

References Cited UNITED STATES PATENTS 3,119,127 1/1964 Taggert 9l A. H.FARRELL, Primary Examiner.

